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The incidence and control of hypocalcaemia in pasture-based systems


Roche, JR, The incidence and control of hypocalcaemia in pasture-based systems, Acta Veterinaria Scandinavica , 97, (SUPPL. 97) pp. 141-144. ISSN 0065-1699 (2003) [Refereed Article]


A large emphasis on precalving magnesium supplementation has substantially reduced the incidence of clinical hypocalaemia in pasture-based systems. Survey data in the major pasture-based systems suggest a 2 to 4% incidence of parturient paresis, although this can vary considerably between farms. Detailed blood measurements under research conditions suggests that approximately 5% of cows are clinically hypocalcaemic (blood calcium < 1.4 mmol/l) and between 30 and 40% of cows are subclinically hypocalcaemic (plasma calcium < 2.0 mmol/l). Systems of control have traditionally been based on preventing the paretic cow, with more emphasis of late being placed on preventing hypocalcaemia. Preventative measures vary, but largely involve either supplementation with magnesium oxide pre-calving, supplementation with calcium carbonate during the colostrum period or a combination of magnesium supplementation precalving and calcium supplementation post-calving. In New Zealand, the use of commercial products that bind calcium is increasing precalving, but is still only practised by a small percentage of farmers. The dietary cationanion difference (DCAD) of pasture is so high and so variable that changes in DCAD sufficient to change blood pH are not practical and very difficult to achieve with consistency. The use of magnesium chloride and magnesium sulphate in preference to magnesium oxide, as precalving magnesium supplements, is increasing.

Item Details

Item Type:Refereed Article
Research Division:Agricultural, Veterinary and Food Sciences
Research Group:Animal production
Research Field:Animal management
Objective Division:Animal Production and Animal Primary Products
Objective Group:Livestock raising
Objective Field:Dairy cattle
UTAS Author:Roche, JR (Dr John Roche)
ID Code:41290
Year Published:2003
Deposited By:Agricultural Science
Deposited On:2006-12-21
Last Modified:2011-09-19

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